Fix encoding issue in check_git_config

tools/check_git_config.py

 #!/usr/bin/env python
 # Copyright 2014 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 """Script that attempts to push to a special git repository to verify that git
 credentials are configured correctly. It also verifies that gclient solution is
 configured to use git checkout.
 
 It will be added as gclient hook shortly before Chromium switches to git and
@@ skipping 93 matching lines @@
 
 def read_git_config(prop):
   """Reads git config property of src.git repo.
 
   Returns empty string in case of errors.
   """
   try:
     proc = subprocess.Popen(
         [GIT_EXE, 'config', prop], stdout=subprocess.PIPE, cwd=REPO_ROOT)
     out, _ = proc.communicate()
-    return out.strip()
+    return out.strip().decode('utf-8')
   except OSError as exc:
     if exc.errno != errno.ENOENT:
       logging.exception('Unexpected error when calling git')
     return ''
 
 
 def read_netrc_user(netrc_obj, host):
   """Reads 'user' field of a host entry in netrc.
 
   Returns empty string if netrc is missing, or host is not there.
@@ skipping 406 matching lines @@
       write_last_configuration(config)
     else:
       logging.warning('Check failed and will be retried on the next run')
   except Exception:
     logging.exception('Unexpected exception when performing git access check')
   return 0
 
 
 if __name__ == '__main__':
   sys.exit(main(sys.argv[1:]))